How to run PowerShell script from Ant

logo-powershellYesterday I was looking for a good recipe of how to run PowerShell script from Ant build file. Unfortunately, it seems that most of the people are looking for an advise on exactly the opposite – how to run Ant from PowerShell. So, I did some trial and error on my own, and here are the results.

The following Ant snippet executes PowerShell script MyScript.ps1 in the current directory and verifies that it did not fail. The result of the script execution is stored in myscript.out property.

<exec dir="." executable="powershell" timeout="5000" failonerror="true"
        outputproperty="myscript.out" errorproperty="myscript.error">
    <arg line="-ExecutionPolicy bypass" />
    <arg line="-File MyScript.ps1" />
        <equals arg1="${myscript.error}" arg2="" trim="true" />
        <fail message="${myscript.error}" />

The main caveat here is the error checking. Despite the failonerror flag, the exec task will not fail in case of many errors – like compilation issues, missing parameters and other runtime errors. This happens because the task verifies invocation of PowerShell itself and not the script execution, which is handled inside PowerShell. The solution is to capture error stream into dedicated property and verify that nothing was actually written there.

Pay attention that if tag (lines 6-13) requires ant-contrib tasks library available. The same condition may be rewritten in less readable form with pure Ant:

<fail message="${myscript.error}">
            <equals arg1="${myscript.error}" arg2="" trim="true" />

Another note is the bypass of default execution policy on line 3. This is not specific to Ant, but rather to PowerShell in general. There are a lot of discussions on the net about the topic, so I won’t cover it here.

Notes on creation of Windows AMI in EC2

AWSCreating AMI from Windows instance in AWS is simple and easy. The whole process is well-documented, yet here are several notes that I made while experimenting.

Running Sysprep Tool
In the VMware world, you can convert a VM to a template at any moment. Deployment of multiple clones is made possible via Customization Specifications mechanism, where you define how to customize the new VM after cloning. As part of the customization process, vCenter will run Sysprep tool – after the instance was already cloned. In contrary, AWS wants you to run sysprep before the cloning, as preparation to AMI creation. You can do that via EC2ConfigService settings (see below) or manually, but former seems to be the preferred and recommended way.
The unwanted side effect of running sysprep on the original instance is that many of the original instance settings (instance name, Administrator account etc.) are actually reset during the cloning process. There are workarounds that can help you to deal with some consequences, but not all of them.

The EC2ConfigService is Windows service provided and installed by AWS, which takes care about a lot of useful customizations behind the scenes. Examples are generation of Administrator password (one that you retrieve via “Connect” button in EC2 Management Console), setting of computer name, display of system information on the desktop wallpaper and a lot more. But the most important task is to deal with instance cloning – that is, make sure that stuff that is supposed to be unique is really unique and make this cloning process simple and easy.
Note that you cannot install this service on a Windows instance imported from other systems (for example, VMware vCenter). You’ll have to start your original instance from AWS AMI if you want to use EC2ConfigService there.

Instance Name
The name of the original Windows instance will be reset during sysprep process to the default semi-random name provided by AWS (in the form of “WIN-<something>”). The only workaround for that is to use “Set Computer Name” from EC2ConfigService settings. This flag instructs EC2ConfigService to (re)set system name according to the internal IP adrress – which remains constant during the instance lifecycle. The resulting name will not become much more readable, but at least it will not change during the AMI creation process. You’ll have to remove this flag manually on the cloned instances to set more meaningful names there.

Administrative Accounts
The Administrator account from the original instance will not make his way to the cloned instances, so any customizations made there will be lost. The workaround is to create an additional account with administrative permissions and perform the desired customizations there. There are many settings that will go this way too (for example, regional settings or pinned taskbar items), but some will survive – desktop shortcuts, windows explorer options and more.
Another tip is to choose “Keep Existing” in the “Administrator Password” section of EC2ConfigService configuration. While it won’t help you to retain current password in the new instances (because Sysprep tool on Windows 2008 resets it anyway), at least the Administrator password of your original instance will not be changed.

AMI Creation Steps
This is not an ultimate guide on how to create AMI, but rather a note/reminder to myself…

  1. Create a new EC2 instance from AWS AMI
  2. Create new administrative account and start using it instead of the build-in one
  3. (optional) Use “Set Computer Name” option from EC2ConfigService settings
  4. Customize your instance – install software, add desktop shortcuts etc.
  5. Start EC2ConfigService settings utility, go to the “Image” tab and perform the following:
    • (optional) Under “Administrator Password” section, select “Keep Existing” option
    • Click “Shutdown with Sysprep” button and confirm the prompt
  6. Wait while the Sysprep process completed and the instance shuts down
  7. Right-click the instance in the EC2 Management Console, choose “Create Image” and follow the instructions

Tip: Disk Size
When you launch an EC2 instance that you plan to convert to AMI later, pay attention to the disk size. Remember that the disk of the AMI must be at least that big, and the same applies to any instance that will be launched from the new AMI. Provisioning 10GB of spare storage in your AMI will cost you $1 per instance per month, which may be kinda painful in the yearly bill (do the math yourself).

How to convert VM hard drive from Thick to Thin Provisioning

Using Thin Provisioning for virtual disks of your VM can save you a lot of useful space on your datastore and significantly speed up maintenance tasks that involve copying or moving of the VMDK files. Apparently, switching from one provisioning format to another can be done easily via Clone Virtual Machine wizard, where Storage tab allows you to specify the virtual disk format for the cloned VM. There you can select either to keep the same disk format as source VM had or choose another one, including Thin Provision. However, the choice of Thin Provision disk format will be silently ignored when the source format is Thick Provisioned and both source and target are located in the same datastore. This behavior is somehow understandable when you think about the underlying implementation, but not user friendly.

So, how can you change the provisioning type of your VM from Thick to Thin anyway? Here is your algorithm.

  • Do you have more than one datastore available? You can migrate your VM to another datastore, modifying the virtual disk provisioning mode on the way, and then migrate it back if needed. This way is covered in details in the second part of KB2014832 article on VMware Knowledge Base.
  • Do you have only one datastore or all your datastores are under the same Storage DRS? You can create a clone of your VM with the help of vCenter Converter Standalone. This tool runs on your desktop and allows you to convert one VM format into another, changing most of the VM setting on the way. This includes change of disk provisioning type from Thick to Thin even when both source and destination are located on the same datastore.
  • Do you prefer the hard and risky ways? If so, dealing with vmkfstools if for you 🙂

How to upgrade Microsoft UAG 2010 SP1 to SP2

How do you upgrade from UAG 2010 SP1 to UAG 2010 SP2? Well, it appears that such upgrade is not as trivial as expected.

First, Microsoft UAG is based on another Microsoft product – Microsoft TMG, – which has to be upgraded separately. Besides that, there is no direct upgrade package for the UAG itself. Thus, the correct upgrade path would be as follows: UAG SP1 => UAG SP1 Update 1 => TMG SP2 => UAG SP2. Of course, the whole process is documented in TechNet – but you have to be aware about this upgrade path first…

There is another caveat in this upgrade. In case you have some UAG trunks configured (and I assume you have some, since what do you need UAG for otherwise?), you have to active UAG configuration after each step in the upgrade process, otherwise you’ll end up without configured trunks – they will disappear silently during the process. Thanks to TechNet forums for solving this one for me!

How to install RDP 6.1 on Windows Server 2003

Microsoft RDP client (aka “Remote Desktop Connection” or “Terminal Services Client”)  allows you to connect from your Windows station to other Windows servers. Version 6.1 was released in 2008 and nowadays many popular tools (such as mRemoteNG) state it as a requirement. Unfortunately, this version is available for Windows XP/Vista and Windows Server 2008, but not for Windows Server 2003.

So, how can you install RDP client 6.1 on Windows Server 2003?

It appears that in March 2011 Microsoft released security update for RDP client 6.0 and 6.1 – which can be installed on Windows Server, since the original RDP client 6.0 is supported there. Now, pay attention to this note in the “more information” section:

Bottom line? Take the official RDP client 6.0, download KB 2481109 for Windows Server 2003 (the security update mentioned above) – and you are ready to run with RDP client 6.1 on your Windows Server 2003!